1. Field of the Invention
The present invention relates to a liquid developer refilling system of a liquid electrophotographic printer and a method thereof, and more particularly, to a liquid developer refilling system of a liquid electrophotographic printer, in which in order to supply any one of concentrated inks and a liquid carrier stored in a cartridge to a corresponding one of a plurality of ink tanks and a carrier tank equipped within the main body of the printer, the structure thereof is improved so that a corresponding valve of a plurality of valves can be automatically connected to the cartridge by matching the corresponding valve to the cartridge after identifying the cartridge installed at a common installation portion which is provided at a main body of a printer, and a method thereof.
2. Description of the Related Art
In general, in a printing device such as a laser printer or a copier, a latent electrostatic image formed on the surface of a photosensitive medium such as a photosensitive belt is developed with a liquid developer composed of a solid toner having a predetermined color and a liquid carrier functioning as a solvent; and the developed image is transferred to a paper.
A conventional liquid electrophotographic printing device includes an ink supplying structure in which ink cartridges and a carrier cartridge are installed at a main body of the printing device. Concentrated inks and a carrier within the cartridges are supplied to a developing unit, and liquid developers required for the printing device are made by mixing the concentrated inks and the carrier. Here, the liquid developers are solutions made by mixing, in predetermined proportions, the concentrated inks composed of powder toners and are supplied from the ink cartridges and liquid carrier supplied from the carrier cartridge. The toners include pigments exhibiting colors of yellow, magenta, cyan, and black, respectively.
However, since the above cartridges supply the concentrated inks or the carrier contained therein to the developing unit via a predetermined passage and a pump, there is a disadvantage in that the passage between the cartridge and the developing unit is long. Also, although the cartridge has a characteristic of a consumable part, a functional part such as an agitator must be installed so that the contents stored in the cartridge do not precipitate. Therefore, the conventional ink delivery system has a disadvantage in which the system is expensive.
In order to reduce the cost thereof, various ink delivery systems have been proposed recently, in which tanks are provided in the vicinity of a developing unit, the functional part such as an agitator can be omitted, and a refill cartridge is installed at the outside of a main body of a printer for supplying a carrier or inks to the tanks.
In a liquid developer circulation process of an ink delivery system, liquid developer which has been recovered at a corresponding circulation tank via a development gap of a developing unit and a drying/condensing unit is transferred from one developing unit to another neighboring developing unit by a circulating photosensitive medium, and is mixed with a different liquid developer. Such a developer mixing event is referred to as cross contamination. Therefore, when printing jobs are repeatedly performed, the purity of the liquid developers of the tanks is not maintained within an allowable range due to the cross contamination, and the liquid developers stored in the circulation tanks become unusable waste developer. Under this situation, the waste developer must be discharged out of the circulation tank, and new inks and new carrier are refilled to fill liquid developers within the allowable purity range. Thus, a waste tank is installed at a printing device for recovering waste developer within the circulation tank. On the other hand, although the waste developer in the waste tank can be recovered to a separate waste bottle installed at the printing device, a method of recovering waste developer by using an empty refill cartridge corresponding to a tendency in which an ink delivery system employs a refill cartridge is under consideration.